1	package antlr;
2	
3	/**
4	 * <b>SOFTWARE RIGHTS</b>
5	 * <p>
6	 * ANTLR 2.5.0 MageLang Institute, 1998
7	 * <p>
8	 * We reserve no legal rights to the ANTLR--it is fully in the
9	 * public domain. An individual or company may do whatever
10	 * they wish with source code distributed with ANTLR or the
11	 * code generated by ANTLR, including the incorporation of
12	 * ANTLR, or its output, into commerical software.
13	 * <p>
14	 * We encourage users to develop software with ANTLR. However,
15	 * we do ask that credit is given to us for developing
16	 * ANTLR. By "credit", we mean that if you use ANTLR or
17	 * incorporate any source code into one of your programs
18	 * (commercial product, research project, or otherwise) that
19	 * you acknowledge this fact somewhere in the documentation,
20	 * research report, etc... If you like ANTLR and have
21	 * developed a nice tool with the output, please mention that
22	 * you developed it using ANTLR. In addition, we ask that the
23	 * headers remain intact in our source code. As long as these
24	 * guidelines are kept, we expect to continue enhancing this
25	 * system and expect to make other tools available as they are
26	 * completed.
27	 * <p>
28	 * The ANTLR gang:
29	 * @version ANTLR 2.5.0 MageLang Institute, 1998
30	 * @author Terence Parr, <a href=http://www.MageLang.com>MageLang Institute</a>
31	 * @author <br>John Lilley, <a href=http://www.Empathy.com>Empathy Software</a>
32	 */
33	/**BlockContext stores the information needed when creating an
34	 * alternative (list of elements).  Entering a subrule requires
35	 * that we save this state as each block of alternatives
36	 * requires state such as "tail of current alternative."
37	 */
38	class BlockContext {
39		AlternativeBlock block; // current block of alternatives
40		int altNum;				// which alt are we accepting 0..n-1
41		BlockEndElement blockEnd; // used if nested
42	
43	
44		public void addAlternativeElement(AlternativeElement e) {
45			currentAlt().addElement(e);
46		}
47		public Alternative currentAlt() {
48			return (Alternative)block.alternatives.elementAt(altNum);
49		}
50		public AlternativeElement currentElement() {
51			return currentAlt().tail;
52		}
53	}
54